Synthesis, analysis and characterizations of Dy³⁺ ions-doped CaBi₂Nb₂O₉ phosphors for optoelectronic device applications

The current study focuses on the synthesis and other detailed studies on CaBi₂Nb₂O₉ (abbreviated CBNO) phosphor doped with Dy³⁺ ions. The aforementioned phosphors were prepared via a solid-state reaction procedure and a comprehensive analysis of the crystal structure, particle morphology, vibrational bands, luminous characteristics, decay and thermal stability of the phosphors was done. Phase identification of the synthesized material was carried out using X-ray diffraction (XRD) technique and the optical bandgap was determined using diffuse reflectance spectra (DRS). The morphological studies and particle size estimation of the phosphor material were conducted using a scanning electron microscope (SEM). Under 452 nm excitation, the photoluminescence (PL) spectra of Dy³⁺-doped CBNO phosphor exhibit three peaks at 482, 576, and 666 nm, which correspond to the transitions ⁴F_9/2 → ⁶H_15/2, ⁶H_13/2, and ⁶H_11/2. The electric dipole–dipole interaction was the main mechanism for concentration quenching for Dy³⁺ ions. The estimated CIE chromaticity coordinates for Dy³⁺ ion-doped CBNO phosphors fall in the white region. The temperature-dependent PL (TD-PL) findings reveals that CBNO phosphors have a considerably superior thermal stability. The results of these investigations suggest that the CBNO phosphors doped with Dy³⁺ ions exhibit promising properties that could be used for prospective w-LEDs and other optoelectronic device applications.